Venetian blinds consist of a plurality of horizontal slats. These slats rest on ladders made of cord, fabric tape, or flexible sheets of sheer material. Blinds have a headrail and bottomrail, the bottomrail being either one solid rail or two parallel rails connected by a cord. The blinds have a lift cord or cords, traditionally connected from the bottomrail through route holes in the slats, to a lift mechanism or cord lock in the headrail. Another arrangement is provided in my U.S. Pat. No. 5,573,051, in which lift cords are placed proximate to the front and rear edges of the slats, and tiny notches or slots are made in the slats for the lift cords to pass through from the bottomrail into the headrail.
Blinds are raised to stack slats at the top by pulling the lift cords through a cord lock, which locks into place by pulling the lift cords laterally to catch the lock and then back to set the lock. Alternately, an axle driven cord collection system may be used for one or more sets of lift cords in place of a cord lock. All the slats in a venetian are typically all tilted the same amount, whether it is open at horizontal, closed at vertical, or somewhere in between. The blind cannot have one portion that is open and another portion which is closed unless the owner turns the slats individually. Yet, there has been a demand for blinds in which the upper half of the blind can be open to allow light to come in and for occupants to see out, while the lower half of the blind is closed to prevent glare or fading and afford privacy to the occupants. The upper half can be open by having the slats tilted at horizontal or by having no slats at all in the upper half of the blind. This invention describes ways of accomplishing this without resorting to the more complicated controls inherent in a bottom and top stacking blind.
In U.S. Pat. No. 7408, Bohrer describes a so-called bottom-up venetian blind in which all slats can be stacked at the bottomrail by means of a pulley assembly. He introduced a movingrail which houses a tilt mechanism and to which the ladders are connected to hold the slats. The operator lifts the movingrail by pulling a lift cord through a pulley assembly, then hooking the cord onto cleats. This design tilts the slats by pulling a tilt cord connected to a tilt mechanism in the movingrail which twists the movingrail and is difficult to operate. The lift cords must be pulled and cleated at an angle to the wall, creating a less streamlined, less neat appearance.
A similar blind is described by Rose in U.S. Pat. No. 12,695. Rose uses a fixed headrail and a movingrail and provides a complex series of hooks and cords to lock the movingrail into place at the headrail. This facilitates the tilting of the slats relative to the movingrail by holding it steady. The mechanism, however, is complicated and uses several pieces of additional hardware not necessary in traditional venetian type blinds. It also requires the blind to be lifted to the headrail to be tilted.
In U.S. Pat. No. 2,283,640, Kwon describes a blind which also uses a movingrail, but with a different lifting and tilting mechanism. The blind is raised from a bottom-stacked position by pulling and cleating two sets of tilt/lift cords simultaneously; the blind is tilted by pulling one set of the cords more than the other. This arrangement requires two-hand operation of the blind, which is difficult in many room settings. It also involves shifting the center of gravity of the blind away from or toward the window, causing a gap between the tilted blind and the window in the first case and causing the stack to drag on the wall or the window in the second case.
Most recently, Levert et al. describe an upwardly deployed blind in U.S. Pat. No. 5,443,108. This design consists of a fixed headrail, a movingrail, and a bottom rail. The tilt assembly is again placed on the movingrail. The blind is raised from a bottom-stacked position by pulling a drawstring in the headrail connected to a cord lock. To tilt the blind, a tilt bar on the movingrail is used. This reduces the twist of the movingrail somewhat, but is very bulky and is potentially awkward to operate because the movingrail is constantly changing position relative to the operator.
These previous inventions allow the operator more choices as to how to stack the blind for the desired combination of light passage and privacy. Yet, they require more controls for the operator to understand and none of these blinds allow some of the slats to be in an open horizontal position while other slats are in a closed tilted position. There is a need for a venetian blind which provides an inexpensive and relatively simple way to leave the top half of the window open. Ideally, this blind will also require a minimum of additional hardware for a fabricator to make blinds with different cording and hole configurations such as slats with route holes in the centerline, slats with hidden holes in the rear of the slats, or slats with no holes. Also the blind should be able to utilize cord ladders, fabric tape ladders, or sheer material sheet ladders.